KIT and mucinous neoplasm: In cancers of the appendix, KIT/c-KIT gene activating mutations occur rarely and are identified in a small number of cases of mucinous adenocarcinomas [12] and in disseminated mucinous tumors grade 2, whereas in well-differentiated neuroendocrine tumors of the appendix, mutations in the KIT/c-KIT gene appear to have a higher frequency [37].